Backup and recovery systems are important features in systems that store crucial data for the usual operations of a business endeavor. For businesses that increasingly depend on data and information for their day-to-day operations, the unplanned downtime that occurs when a computer system needs to be restored to an earlier configuration can impact financial goals and reputations. Rapid, simple, and accurate recovery operations are valuable features of a backup and recovery system.
In various situations, a recovery can be performed to restore the data used by an application after a system has failed. In anticipation of such failures, the data used by the application can be stored from time to time on backup storage systems. The backup copies can be made by querying the application to obtain files, data records, email messages, or similar objects that are used by the application, and copying those objects onto a backup storage system for preservation.
Such backups of logical objects, however, impose overhead costs on the application, which must assist in the continually ongoing backup operations. The application must be diverted from regular operations to assist the backup operations, providing the relevant files to the backup operations for storage. Moreover, such backups generally suffer from a lack of consistency: while one particular file is being backed up, a related file may be modified or deleted by the application. The resulting set of backup files can thus be a set of files (or email messages or other logical objects) that do not bear a consistent temporal relationship with each other.